catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ia9932efb6a9335e80b3f2376d2d62e1b65866f44
diff --git a/src/manufacturingcommands.cpp b/src/manufacturingcommands.cpp
index 2417955..7ed7506 100644
--- a/src/manufacturingcommands.cpp
+++ b/src/manufacturingcommands.cpp
@@ -145,7 +145,7 @@
                     *getSdBus(), callbackMgrService, callbackMgrObjPath,
                     callbackMgrIntf, retriggerLedUpdate);
             }
-            catch (sdbusplus::exception_t& e)
+            catch (const sdbusplus::exception_t& e)
             {
                 return IPMI_CC_UNSPECIFIED_ERROR;
             }